The deterioration of the gatehouse sandstone required complete reconstructions in 1938.[4] These restorations were completed under the direction of National Park Service architect Thomas T. Waterman.[5]

Four of the original Bullfinch gateposts from the former fence around the Capitol grounds were moved to Constitution Avenue at the same time as the gatehouses. The posts are twelve feet high and five feet square.[6]

The gatehouses are small temple-like stone structures, with rough-coursed masonry (rustication) on the sides and rear and a small Tuscan order porch on the front. The material is Aquia Creek sandstone of a rather poor grade. The east gatehouse bears two high water marks carved into the stone to commemorate flooding in 1877 and 1881.[5]